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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_002_001_087">&nbsp;</a>NAME</h4><blockquote>
typeahead - control checking for typeahead
</blockquote><h4><a name = "tag_002_001_088">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

#include &lt;<a href="curses.h.html">curses.h</a>&gt;

int typeahead(int <i>fildes</i>);
</code>
</pre>
</blockquote><h4><a name = "tag_002_001_089">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>typeahead()</i>
function controls the detection of typeahead during a refresh, based on the
value of <i>fildes</i>:
<ul>
<p>
<li>
If <i>fildes</i> is a valid file descriptor, typeahead is enabled during
refresh; Curses
periodically checks <i>fildes</i> for input and aborts the refresh if any
character is available.  (This is the initial setting, and the typeahead file
descriptor corresponds to the input file associated with the screen created by
<i><a href="initscr.html">initscr()</a></i>
or
<i><a href="newterm.html">newterm()</a></i>.)
The value of <i>fildes</i> need not be the file descriptor on which the refresh
is occurring.
<p>
<li>
If <i>fildes</i> is -1, Curses does not check for typeahead during refresh.
<p>
</ul>
</blockquote><h4><a name = "tag_002_001_090">&nbsp;</a>RETURN VALUE</h4><blockquote>
Upon successful completion,
<i>typeahead()</i>
returns OK.  Otherwise, it returns ERR.
</blockquote><h4><a name = "tag_002_001_091">&nbsp;</a>ERRORS</h4><blockquote>
No errors are defined.
</blockquote><h4><a name = "tag_002_001_092">&nbsp;</a>SEE ALSO</h4><blockquote>
<xref href=terminalinput><a href="intov.html#tag_001_005">
Input Processing
</a></xref>,
<i><a href="doupdate.html">doupdate()</a></i>,
<i><a href="getch.html">getch()</a></i>,
<i><a href="initscr.html">initscr()</a></i>,
<i><a href="curses.h.html">&lt;curses.h&gt;</a></i>,
<b>XBD</b> specification, <a href="../xbd/termios.html#tag_008_002"><b>Parameters that Can be Set</b>&nbsp;</a> .
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
<br> [ <a href="../index.html">Main Index</a> | <a href="../xshix.html">XSH</a> | <a href="../xcuix.html">XCU</a> | <a href="../xbdix.html">XBD</a> | <a href="../cursesix.html">XCURSES</a> | <a href="../xnsix.html">XNS</a> ]

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